US2201604A

US2201604A - Sheet feeder

Info

Publication number: US2201604A
Application number: US212284A
Authority: US
Inventors: Backhouse Headley Townsend
Original assignee: Individual
Current assignee: Individual
Priority date: 1937-08-26
Filing date: 1938-06-07
Publication date: 1940-05-21
Anticipated expiration: 1957-05-21

Description

May 21, 1940- H. 'r. BACKHOUSE srmm FEEDER Filed June 7,v 193a ATTORNEYS Patented May 21, 1940 UNITED STATES SHEET FEEDER Headley Townsend Backhouse, London, England Application June 7, 1938, Serial No. 212,284 In Great Britain August 26, 1937 9 Claims.

This invention relates to improvements in sheet feeders, and is concerned with machines for feeding sheets of paper, card or the like seriatim from the top of a pile to a printing or other machine,

particularly in stream formation.

The invention provides a machine of the above kind comprising in combination a feed roll or band mounted above the pile and having its upper side movable in the feeding direction and its underside movable in the opposite direction, means for separating each top sheet in turn by its rear edge (considered in relation to the direction of the final feed) and presenting the separated edge to the underside of the feed roll or hand and means for maintaining the separated sheet in contact with the roll or band so that it may be carried round with the roll or band and delivered from the upper side thereof, the separating means and the roll or band being operable at such relative speeds that the sheets are fed by the roll or band in the form of a continuous stream with the front edge of each sheet overlying one or more of the preceding sheets.

It will be appreciated that by reason of the fact that the machine according to the invention feeds the sheets with their front edges overlying one or more of the preceding sheets the machine operates in a manner different from that of the well known stream-feeders which feed the 0 sheets with'their front edges underlying one or more of the preceding sheets. This arrangement of the stream of sheets fed by the present machine has the advantage that as the sheets reach any particular station, for example the lay-board of a printing press, the leading sheet may eadily beseparated from the succeeding sheet by arranging the. lay-board or other station to be slightly below the level of the line of sheets when the leading sheet will fall onto it substantially clear of the succeeding sheet. I

This feature is used to advantage in the preferred form of the invention in which a machine as described above is provided with a sheet registering conveyor located slightly below the level of the stream of sheets and onto which each leading sheet in turn is fed from the feed roll or band, either direct or by means of ,an intermediate sheet conveyor, the sheet registering conveyor being itself movable while each sheet is on it to draw the sheet sideways up to a side registering gauge.

The invention includes the method of feeding the machine and carrying out similar separating and lifting operations on the next sheet before the first has completely left.the pile so that the sheets are forwarded in the form of a continuous stream with the front edge of each sheet overlying the rear edge of the preceding sheet.

One specific machine according to the invention and the method of operation thereof will now be described by way of example and with reference to the accompanying diagrammatic drawingin which Fig. 1 is a perspective view of the machine with a pile of paper.

Fig. 2 is a side view showing the feed roll and sheet separating means in a position ready to separate the top sheet.

Fig. 3 is a view corresponding to Fig. 2 showing the rear edge of the sheet lifted.

Fig. '4 is a similar view showing the lifted engaged by the feed roll.

Like reference characters indicate like parts in the several figures of the drawing.

In this example the sheets I are -separated singly from the top of the pile 2 by meansof lifting suckers 3 which operate over the rear edge of the pile 2. The initial position of the suckers in which they are ready to separate the uppermost sheet and are gripping the sheet near its rear edge is shown diagrammatically in Fig. 2. From sheet this position the suckers move upwardly and forwardly to the position shown in Fig. 3 carrying with them the rear portion of the sheet towards the underside of the revolving feed drum 4 which is mounted above the pile with its axis transverse thereto. In this position the lifted edge of the sheet is moved toward the drum by a swinging roller 5.

After the sheet has been brought under the control of the roller 5 the suction is released from the suckers and the suckers are rapidly withdrawn in directions first upwardly into the position shown in Fig. 4, then rearwardly and downwardly and finally forwardly into'the position shown in Fig. 2 ready to engage .the next sheet and repeat the cycle. In the meantime roller 5 has pressed the sheet against the drum 4 and the sheet is then carried forward between the drum, which is positively driven, and the roller. The timing of the cycle of operations carried out by the suckers and the peripheral speed of movement of the feed drum are so chosen that each successive sheet overlaps to a predetermined extent the preceding sheet on the drum.

Two or more lifting suckers may be employed spaced apart along the rear edge of the pile and separation may be assisted by combing wheels or by an air blast or both and the lifting suckers may be given movements upwards and away from one another as described in my prior Patent No.

2,108,702, dated February 15, 1938, to stretch the lifted sheet.

The sheets are maintained in contact with the upper part of the drum by means of bands 6 and after they have passed over the top of the drum they are delivered to a conveyor 1 of known pattern along which they pass towards the printing press in overlapped formation with the front portion of each sheet overlapping a portion of the preceding sheet. At the end of the conveyor 'l' the sheets are delivered to a second conveyor 8 the rear end of which is arranged at a level slightly-below that of the front of the conveyor I. The sheets therefore, as they in turn leave the conveyor 1, drop onto the conveyor 8 and are substantially relieved of the weight of the succeeding sheets although they may, to some extent, continue to support the front edges of the succeeding sheets.

The conveyor 8 is a self-contained unit with its front end close to the front lays 9 of the printing press and comprises a frame l which is arranged for lateral reciprocating movement by any suitable means, which may include a bell-crank lever l I, pivoted upon a frame bracket I 2 and arranged to be actuated by a link l3 that is reciprocated once for each sheet fed.

The reciprocatory movement of the conveyor 8 is timed so that as soon as the whole of the leading sheet has dropped onto it the conveyor is moved sideways, while still conveying the sheet,

forwardly, to draw the sheet up against an adjustable sidelay stop l4 that is also supported on backet l2. The control of the sideways movement of the sheet, if desired, may be assisted by the use of smoothers or ball controls of known pattern and the lateral registration is effected before or at about the same time as the arrival of the front edge of the sheet at the front lays 9. After front and side registration has been effected the sheet is taken into the press by known means and during this operation the conveyor 8 is returned to its original position in readiness for th next sheet.

It is to be understood that the invention is not restricted to the precise constructional details set forth. Thus for example the feed roll '4 may be omitted and its place taken by the rear end of the conveyor 1 which is conveniently enlarged in its vertical dimension for that purpose.

Having thus described my invention, I claim:

1. In a sheet feeder, means for forwarding sheets in stream formation, each sheet overlap- Ding the preceding sheet, a forwardly moving conveyor adapted to receive the foremost sheet of the stream as it leaves said forwarding means, and means for shifting said conveyor sidewise to side register the sheet.

2. In a sheet feeder, means for forwarding sheets in stream formation, each sheet overlap-' ping the preceding sheet, a forwardly moving conveyor adapted to receive the foremost sheet of the stream as it leaves said forwarding means, a frame upon which said conveyor is mounted, a side guide, and means for shifting said frame sidewise to draw the foremost sheet against said side guide.

3. A method. of feeding sheets to a printing press or the like, which comprises forwarding the sheets in stream formation with each sheet overlapping the preceding sheet, dropping the foremost sheet of the stream onto a separate forwardly moving conveyor, and shifting the conveyor sidewise for sheet registration purposes.

4. In a sheet feeder, means for forwarding sheets in stream formation with the rear end of each sheet overlapped by the forward end of the next succeeding sheet, a forwardly moving conveyor the rear end of which is arranged at a lower level than said forwarding means, said conveyor being adapted to receive the foremost sheet of the stream as it drops from said forwarding means, and means for shifting said conveyor sidewise to side register the sheet.

5. In a sheet feeder, means for forwarding sheets in stream formation with the -rear end of each sheet overlapped by the forward end of the next succeeding sheet, a forwardly moving conveyor the rear end of which is arranged at a lower level than said forwarding means, said conveyon being adapted to receive the foremost sheet of the stream as it drops from said forwarding means, a frame upon which said conveyor is mounted, a side guide, and means for shifting said frame sidewise to draw the foremost sheet against said side guide.

6. In a sheet feeder, means for forwarding sheets in stream formation with the rear end of each sheet overlapped by the forward end of the next succeeding sheet, a forwardly moving conveyor arranged to receive the foremost sheet of the stream, and means for shifting said conveyor sidewise after the foremost sheet is supported thereupon, said sidewise movement of the conveyor being initiated before the forward travel of the sheet upon the conveyor is terminated.

7. In a sheet feeder, means for forwarding sheets in stream formation with the rear end of each sheet overlapping by the forward end of the next succeeding sheet, a forwardly moving conveyorarranged to receive the foremost sheet of the stream, front lays into engagement with which said conveyor is adapted to move the foremost sheet, and means for shifting said conveyor sidewise after the foremost sheet is supported there- .upon, said sidewise movement being initiated before the forward end of the sheet engages said front lays.

8. In a sheet feeder, means for forwarding sheets in stream formation with the rear end of each sheet overlapped by the forward end of the next succeeding sheet, a forwardly moving endless belt conveyor adapted to receive the foremost sheetof the stream as it leaves said forwarding means, a frame comprising front and rear rollers over which said belt runs, and means for shifting said frame sidewise to draw said belt sidewise for side registering the foremost sheet.

9. In a sheet feeder, means for ,forwarding sheets in stream formation with the rear end of each sheet overlapped by the forward end of the next succeeding sheet, a forwardly moving endless belt conveyor adapted to receive the foremost sheet of the stream as it leaves said forwarding means, front lays adapted to be engaged by the foremost sheet underthe influence of the forward impetus imparted to it by said belt, a frame comprising front and rear rollers over which said belt runs, and means for initiating sidewise movement of said frame before the foremost sheet strikes said front lays.

HADLEY TOWNSEND BACKHOUSE;